ruby on rails - undefined method `+' for nil:NilClass spree -

i running spree app.

i getting below error when try add product in cart.

undefined method `+' nil:nilclass 

this error comes when add option types , variants of same product.

i not sure what's going wrong here, because not doing changes in code or something.

this extracted source shows.

   if quantity.between?(1, 2_147_483_647)     begin       order.contents.add(variant, quantity, options)     rescue activerecord::recordinvalid => e       error = e.record.errors.full_messages.join(", ")     end 

here's order controller's populate function.

# adds new item order (creating new order if none exists) def populate   order    = current_order(create_order_if_necessary: true)   variant  = spree::variant.find(params[:variant_id])   quantity = params[:quantity].to_i   options  = params[:options] || {}    # 2,147,483,647 crazy. see issue #2695.   if quantity.between?(1, 2_147_483_647)     begin       order.contents.add(variant, quantity, options)     rescue activerecord::recordinvalid => e       error = e.record.errors.full_messages.join(", ")     end   else     error = spree.t(:please_enter_reasonable_quantity)   end    if error     flash[:error] = error     redirect_back_or_default(spree.root_path)   else     respond_with(order) |format|       format.html { redirect_to cart_path }     end   end end 

please me out here.

you need ensure values of variant, quantity , options before sending them spree.

the fact error considered bug on side, since you'd expect nice error message saying "variant nil" or like.

to fix problem though, i'd check these values valid ones before sending them spree.